The present teachings are predicated upon providing an improved disc brake system for use with vehicles. For example, the disc brake system may be used with almost any vehicle (e.g. car, truck, bus, train, airplane, or the like). Alternatively, the disc brake system may be integrated into assemblies used for manufacturing or other equipment that require a brake such as a lathe, winder for paper products or cloth, amusement park rides, or the like. However, the present teachings are most suitable for use with a passenger vehicle (i.e. a car, truck, sports utility vehicle, or the like).
Generally, a braking system includes a rotor, a caliper body, a support bracket, an inboard brake pad, and an outboard brake pad that are on opposing sides of the rotor. The caliper body further includes one or more fingers, a piston bore, and a bridge that connects the one or more fingers to the piston bore. The piston bore houses a piston. The piston bore has a bore axis that the piston moves along during a brake apply and a brake retract. The piston bore may include a fluid inlet, a closed wall, a front opening, and a cylindrical side wall that includes a seal groove located near the front opening. Typically, the fluid inlet is located in the closed wall of the piston bore so that when pressure is applied the fluid will flow into the piston bore. During a pressure apply the fluid will push the piston towards the front opening and into contact with a brake pad. However, during a pressure apply the piston and/or brake fluid may be heated through heat transfer from the brake pad. Some of the heat may be dissipated through movement of the vehicle, but when the brakes are aggressively applied to slow the vehicle or an extended brake apply is used, and then the vehicle is stopped for an extended period of time the heat from the brake pads may boil the brake fluid. The boiling of the brake fluid may damage the braking system.
Generally, most systems do not include any device that cools the brake fluid and/or attempts to prevent heat transfer from the brake pads to the brake fluid. Examples of such braking devices are disclosed in U.S. Pat. Nos. 4,401,012; 4,928,579; 4,995,482; 5,009,291; 5,355,774; 5,988,044; 6,401,596; 7,344,006; and 7,905,335; U.S. Patent Application Publication Nos. 2004/0094375 and 2005/0194220; and foreign Patent Document Nos. JP64/022657; WO2005057055; and WO2006127877 all of which are expressly incorporated herein by reference for all purposes.
What is needed is a heat transfer preventer that can attach to the piston, the brake pad, be used as a shim between the piston and a brake pad, or a combination thereof so that heat is not transferred through the piston into the brake fluid. What is needed is a device that assists in preventing brake fluid from becoming heated after an extended brake apply or an aggressive brake apply, when movement of the vehicle is subsequently terminated. What is further needed is a heat transfer preventer that fits into a small packing space while maximizing conduction and/or convection of heat away from the brake pads, the piston, or the brake system. What is further needed is a device that prevents heat transfer from the brake pads to the piston, and can withstand repeated brake applies.